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K Nielsen

Publications and source records attributed to K Nielsen.

At least 235 records · Page 13Linked to original sources
PubMed1986

Stereological estimates of nuclear volume correlated with histopathological grading and prognosis of bladder tumour.

The aim of this retrospective study is to provide morphometric data which make grading of urinary bladder tumours objective and reproducible by stereological estimation of nuclear volume using the principle of estimating of the volume of particles of arbitrary shape. The study includes 92 specimens: 12 from normal bladder mucosa, and 80 from bladder tumours (15 grade I, 45 grade II, 19 grade III and one grade IV according to Bergkvist et al. 1965). After standard fixation, embedding, sectioning and hematoxylin-eosin staining, an unbiased estimate of the mean volume of nuclei sampled with a change proportional to the volume: (Formula: see text) was calculated. Here l0 is the length of the intercept through a test point hitting a nucleus measured in a random direction through the test point. The weighted means of nuclear volume in bladder tumours are spread over a wide range and show a strong correlation with the Bergkvist grade. Moreover, the relationship between the weighted mean volume of nuclei in bladder tumours and the prognosis is very good. Only one of 35 patients with a mean nuclear volume below 300 micron 3 died of bladder cancer whereas 18 of 19 patients with a mean nuclear volume above 500 micron 3 developed invasives tumours or died of their disease. This simple and fast estimate of nuclear volume seems to provide objective data of high prognostic value.

Adult↗
PubMed1986

The persistent infection of a canine thymus cell line by equine infectious anaemia virus and preliminary data on the production of viral antigens.

Equine infectious anaemia virus (EIAV) was adapted to the Cf2Th cell line, a heterologous malignant line from canine thymus. A persistent infection was monitored for 100 serial passages by demonstrating the presence of virus and viral antigens at each 10th passage by electron-microscopy, immunodiffusion and immunofluorescence. Chromosome analysis of EIAV-infected cells indicated they had a karyotype resembling the control cells of similar passage history. Virus-infected cells, grown in roller cultures for 65 days without subculturing, continuously produced viral antigens into supernatant fluids which were harvested every 3-4 days. Antigen peaks were observed at approximately 12-day intervals. Immunoprecipitin lines of identity were demonstrated between ether-extracted antigens from virus-infected canine cell line and known positive EIAV antigen extracted from infected equine spleen and a commercial source. Replication of a non-oncogenic retrovirus (EIAV) resulted in the continuous release of viral antigens from a persistently infected and infinite cell line.

Animals↗
PubMed1986

Solitary cyst and clear cell adenocarcinoma of the kidney: report of 2 cases and review of the literature.

We report 2 cases of a solitary simple cyst of the kidney harboring clear cell adenocarcinoma in the wall of the cyst. Cysts of the kidney may be divided into solitary cysts, that is large, unilocular cysts with a thin wall, and multilocular cysts, that is sharply demarcated multilocular epithelial-lined cysts with compression of the adjacent renal parenchyma. There are 4 types of tumor and cyst that occur in the same kidney, and our cases belonged to type 3. Suspicion of malignancy was raised by preoperative cytological examination of the fluid of the cysts. Perioperatively, however, no gross evidence of malignancy was found in either case. Frozen section biopsy in case 1 failed to confirm the diagnosis. The cysts were removed by partial nephrectomy. Patient 1 died within 2 years of widespread metastases. Patient 2 had undergone nephrectomy and was well. Based on the literature and our findings we strongly recommend the surgical approach of partial nephrectomy followed by total nephrectomy when the diagnosis has been confirmed.

Adenocarcinoma↗
PubMed1986

Accuracy in core biopsy of the prostate. An autopsy study.

In this autopsy study the predictive values of positive and negative tests of core biopsies of the prostate were investigated. Core biopsies, which were performed after evisceration, were compared with macroscopic and microscopic findings of the entire prostatic gland. Of 107 investigated patients, 100 contained prostatic tissue in the core biopsies. In 11 patients the core biopsies contained carcinoma. All these patients had carcinoma in the tissue sections from the prostate. In 89 patients the core biopsy did not contain carcinoma. 88 of these patients had no carcinoma in the tissue sections from the entire specimens. However, in 1 patient a highly differentiated acinar adenocarcinoma was found. From these results the predictive value of a positive test is 11/11 = 100%, and the predictive value of a negative test is 88/89 = 98.5%. Core biopsy is a suitable method in diagnosing prostatic diseases and gives a very high accuracy when the core biopsy contains prostatic tissue.

Adenocarcinoma↗
PubMed1986

A method for preparation of IgA from bovine mammary secretions.

A method for preparing purified IgA from bovine mammary secretions is described. Whey was initially fractionated by gel filtration and fractions containing IgA were pooled, concentrated and digested with pepsin. The digest was rechromatographed on the same type of gel twice and the resulting IgA preparation tested for purity by an enzyme immunoassay procedure. Five different preparations tested were found to contain no measureable IgM or IgG2 and 0.8% to 1.1% IgG1 on a weight basis. If colostral whey was digested with pepsin prior to chromatography, the IgA preparations contained 1.1% to 2% IgG1 and no measureable IgM and IgG2. The procedure provides a reasonably easy method of eliminating most of the contaminating IgG1 (dimeric) and allows preparation of quantities of IgA for immunochemical studies and standardization of serological techniques.

Animals↗
PubMed1985

Protein constituency of unbound fraction of bovine serum applied to anion exchange columns at different pHs and molarities with or without ethylenediamine tetraacetic acid. Application to preparation of bovine IgG1.

Ethylenediamine tetraacetic acid disodium salt (EDTA) was found to be an important addition to anion exchange buffers in terms of the profile and amounts of eluted bovine serum proteins. Hydrogen ion concentration and buffer composition were important when different types of anion exchanger (DEAE 52 cellulose and QAE Sephadex A 50) were used for separation of bovine serum proteins as functional groups of the different anion exchangers did not behave similarly and were therefore not interchangeable. These findings applied to the purification of bovine serum IgG1 amounting to 15 to 25% of the total IgG1 was accomplished using QAE Sephadex A 50 anion exchange chromatography. This was followed by absorption of the IgG1 fraction with Staphylococcus aureus containing protein A to remove minor IgG2 contaminants and gel filtration to exclude traces of the third component of complement (C3).

Animals↗
PubMed1985

Preparation of heavy chain specific antisera to bovine IgA, IgM, IgG1 and IgG2.

Goats, guinea pigs and rabbits were immunized with bovine IgM or with intact molecules, heavy chains, Fc portions or light chains of bovine IgG1 and IgG2. Rabbits and guinea pigs were immunized with bovine secretory IgA. Goats and guinea pigs produced heavy chain specific antisera to intact IgM whereas rabbits produced anti-light chain antibody and in one instance anti-alpha 2-macroglobulin antibody in addition to the anti-mu response. Goats and guinea pigs produced antisera to bovine IgG1 and IgG2 and their Fc portions that needed little absorption to render them monospecific for the heavy chain. In addition to antibody to the heavy chains, rabbits produced anti-light chain antibody when immunized with intact IgG1 or IgG2 molecules. These latter sera, and those produced by rabbits immunized with Fc portions of IgG1 or IgG2 required extensive absorption before they were monospecific for their respective heavy chains. Heavy chains were poor immunogens in all three species. Rabbits immunized with IgA produced both anti-alpha and anti-light chain antibodies while guinea pigs produced sera with antibody activity to the alpha chain only.

Animals↗
PubMed1985

Changes in symptoms and colpo-cystourethrography in 35 patients before and after total abdominal hysterectomy: a prospective study.

35 women, referred for simple total hysterectomy, were evaluated pre- and postoperatively for bladder suspension and urodynamic changes. Although all patients denied urological problems, more than half of the patients had some degree of stress and/or urge incontinence. 40% had radiological signs of bladder suspension defects. At postoperative examination the symptomatology of incontinence had declined but the radiological pathologic findings had increased. On this basis it may be concluded that it is unpredictable what happens to the bladder and its suspension following simple hysterectomy.

Adult↗
PubMed1985

A "dipstick" enzyme immunoassay for detection of antibody to Brucella abortus in cattle sera.

An enzyme immunoassay that utilizes antigen bound to a matrix which can be removed from the substrate to stop development is described. The assay which is performed in glass or plastic disposable tubes uses Gel-Bond film strips for attachment of antigen. The only equipment requirements are a rotary shaker and a spectrophotometer (optional). The antigen coated strips are passed through a series of tubes containing test serum, wash solution, antibody-enzyme conjugate, wash solution and substrate-chromogen taking about 45 minutes to perform. In testing sera with or without antibody to Brucella abortus a very high correlation existed between same day tests and tests performed over several days as well as with data on the same sera obtained by an enzyme immunoassay in a microtiter format.

Animals↗
PubMed1985

Cleavage of bovine immunoglobulin G1 in whey by an extracellular material from Brucella abortus.

Culture extracts of in vitro grown Brucella abortus were demonstrated to cleave a part of the Fc portion of bovine immunoglobulin G1 in whey but not in serum or as a purified protein from serum. Supernates from Strains 19 and 2308 of B. abortus were both capable of this hydrolysis whereas living cells were not. The cleavage process was independent of antibody activity to B. abortus, appeared to require factor(s) found only in some whey samples and was ineffective with the other bovine immunoglobulins.

Animals↗
PubMed1985

A class capture enzyme immunoassay for immunoglobulin level determinations in bovine sera.

An enzyme immunoassay for determination of individual isotype concentrations in bovine serum was developed. Polystyrene tubes were coated with affinity purified goat antibovine IgA, IgG1, IgG2 or IgM, washed and then incubated with purified isotypes to ascertain crossreactivity and sensitivity limits. Bound isotype was detected using the homologous affinity purified antibody conjugated to horseradish peroxidase and hydrogen peroxide-2,2-azino-di-(3-ethylbenzthiazoline sulfonic acid), as the substrate/chromogen. A standardized serum was diluted and used as a control for comparison. Several dilutions were used initially, however, determinations may be made with a single dilution, 1:200, for all isotypes. Results for 100 sera were compared to data obtained with the same samples using a radial immunodiffusion technique. A low correlation coefficient was noted between results from the two assays. Day to day variation and within test repeatability were determined for both assays using ten samples. For the enzyme immunoassay method, day to day variation for IgA, IgM, IgG1 and IgG2 determinations was 17.5, 19.3, 7.6 and 7.3% while variation in repeatability (within a test) was 6.2, 5.9, 3.3 and 4.5%, respectively. Day to day variation for the single radial immunodiffusion test for IgA, IgM, IgG1 and IgG2 was 15.4, 26.0, 11.5 and 18.3% and variation repeatability (within a test) was 11.6, 13.9, 5.9 and 8.3%, respectively. The procedures consistently detected 0.1 micrograms of immunoglobulin whereas the radial diffusion sensitivity limit was approximately 500 micrograms.

Animals↗